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恐龙是生活在距今2.25亿年至7000万年前的中生代的一类爬行动物。它们主要生活在当时的陆地上和湖泊中。大多数恐龙的身体十分庞大,最大者估计可重达50吨。此外,还有能在海中生活的鱼龙和蛇颈龙,以及空中飞行的飞龙和翼手龙。它们在中生代成了陆地上,天空中和海洋里的主人。难怪有人称中生代为“龙的时代”。但好景不长,到了中生代末期,曾称雄一时的恐龙却“突然”地消失了。关于它们的消失,说法不一,至今仍是一桩悬案。多数人认为是由于当时地壳活动强烈,火山喷发,造成水陆分布的改变和气候的变化,处于
Dinosaurs are Mesozoic reptiles that lived 225 million years to 70 million years ago. They mainly live on land and lakes at that time. Most dinosaurs are very large bodies, with the largest estimated to weigh up to 50 tons. In addition, there are fish and plesiosaurus that can live in the sea, as well as the flying dragon and pterodactyl in flight. They were masters of the Mesozoic on land, in the sky, and in the sea. No wonder some people call Mesozoic “Dragon Age”. But it did not last long, and by the end of the Mesozoic Era, dinosaurs, once dominating, had disappeared “suddenly”. With regard to their disappearance, different opinions have remained a pending case to this day. Most people think that due to the strong crustal activity at that time, volcanic eruptions, resulting in changes in land and water distribution and climate change, at